


The Hybrid Child

by phantom_empress



Category: Kuroko no Basuke | Kuroko's Basketball
Genre: Fluff, Humanoid Kuroko!, Hybrid Child AU!, Hybrid Kuroko!, M/M, One Shot, and a bit of angst
Language: English
Status: Completed
Published: 2016-01-31
Updated: 2016-01-31
Packaged: 2018-05-17 10:31:45
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,680
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5866009
Author URL: https://archiveofourown.org/users/phantom_empress/pseuds/phantom_empress
Summary: <blockquote class="userstuff">
              <p>It was his first humanoid hybrid, a small blue creature with black feline features produced in his laboratory. Seijuro named the subject Kuroko Tetsuya.</p>
            </blockquote>





	The Hybrid Child

It was his first humanoid hybrid with advanced genetic codes and reflexes. A small blue creature with black feline features, produced in his laboratory. It was a long and tedious process with an outstretched wait and patience. They didn't know if it will be a success when they first designed and fertilized its egg in the test tube. But it had grown overnight. Enough to transfer it to a bigger preternatural environment of a glass tank, with its great future in their minds.

Seijuro named the subject Kuroko Tetsuya. Kuroko pertaining to its murky ears and tail and because in a way it was Seijuro's first child. Tetsuya didn't carry much meaning when he chose it because it was a pretty common name amongst Japanese males.

The next day after he announced its name to his colleagues in the lab, Shintarou found it exhibiting signs of life. It was alive.  
Tetsuya's growth halted when it was almost as long as Seijuro's hands, which wasn't much considering what he expected of it. So as a last attempt, they removed it from the container to let it acclimate to the normal human habitat. A dangerous endeavor as it left the creature vulnerable and insecure.

But when Seijuro held it in his hands, it responded positively to the warmth reflex and tried to hide itself in it. The light reflex was positive too as it couldn't open its eyes and hid its face into Seijuro's palms when Shintarou shone the light pen.

It's measurements increased yet again the next day when Seijuro measured him inside the incubator they had left him in the previous night. But Tetsuya didn't grow anymore for the next week.

Seijuro gave everyone a month off and decided to investigate on it himself from inside his house. Tetsuya's vitals were normal if not a bit on the lower side, but it breathed and had good responses to stimuli.

Seijuro filled himself a coffee container and heated a convenience store bento, taking it down to his personal lab in the basement, where a stunted Tetsuya resided, along with some other supplies he had stayed up last night preparing. He didn't appreciate being disturbed even if it was by his own basic needs such as drinking and eating.

He punches in a code and scans his eye before entering. The first thing he sees is Tetsuya standing with his hands flat against the incubator wall, eyes fixated at the entrance as if he had been waiting on him. He probably recognized him from the various tactile familiarities he had with Seijuro. But what had Seijuro putting aside all his accessories were those bright blue eyes that Tetsuya had somehow managed to open by himself. He knew that they were blue since he had designed its genes, but he never really expected them to look so beautiful when alive.

He places his hand near Tetsuya, separated by the incubator wall. As he hypothesized, it reacts by rubbing its face against it. Despite the container being warm it still craved human contact.

Seijuro chuckles. "Hold on a sec. You need to be dressed before stepping outside." He opens the box he had brought earlier from his room, and takes out the micromanaged shirt and pants he had tailored last night.

The moment his fingers touch Tetsuya's warm skin, it tries to latch onto it and snuggles closer. "Easy there." Seijuro couldn't help but laugh quietly at it.

  
No, him. It was living and human. Maybe a little different since its origin but if it made him want to protect it, then it was definitely a him.

"There. We're good now." Seijuro says when he's finally managed to dress Tetsuya and holds out his hand for him to climb on. But Tetsuya bundles up the tip of his middle and index fingers to his chest. "Tetsuya, come." It stares a while at him, unblinking and uncomprehending. Seijuro continues to beckon him with his fingers and words and Tetsuya eventually rotates himself to sit on his palm, still not letting the fingers go. He probably couldn't speak or understand what Seijuro spoke because he hadn't learnt how to. Though he should have tried to. Seijuro still wasn't sure if he could speak at all despite it being a part of his DNA.

The human growth hormone though was not working properly. Its secretion was sparse and malfunctioned. Seijuro wanted to wait a little longer before incising and prodding the endocrine gland. Tetsuya perpetually stared at him as he wrote down possible culprits interrupting his hybrid's growth. Decisions were going to be caveated since it involved a living creature.

He makes a list of a few more basic physical tests and says, "Up for a few experiments?" Tetsuya doesn't respond but his ears immediately spasm on hearing him directly for the first time, wholly conscious.

"Too loud?" He sits down, so, Tetsuya didn't have to crane his neck. This round, his ears stand straighter and more alert on his head. Seijuro pats his head and kneads behind his ears. After a few minutes, to both of their surprise, Tetsuya purrs. "Nyaa~"

So, he could speak after all. And exhibit surprise and shock if his outsized eyes were to be deliberated. "Don't worry, Tetsuya. You're a good boy." Seijuro placates kindly.

Next, he opens the bento he had brought and pushes it towards Tetsuya. "You should eat something other than drinking milk." He remains unreactive, blinking a few times at Seijuro and then the bento.

"Like this, Tetsuya." Seijuro holds the chopstick and eats the rice as slowly as he could to make him understand.

Seijuro frowns when Tetsuya doesn't make any attempts to put the rice in his mouth and just curiously stares at him chewing it.

After a thoughtful moment, Seijuro puts down his chopsticks and nudges Tetsuya's mouth open with his index, the hard edge of his teeth brushing against Seijuro's tip. But what was most fascinating was that as he explored further he found that almost all of Tetsuya's milk teeth had already grown out. The only plausible reason for him to not chew was because he never had. He still only sucked at Seijuro's finger.

"Try to bite, Tetsuya." Seijuro illustrates by baring his own teeth as he moved his lower jaw allowing his teeth to clack against each other. "Bite."

Tetsuya looks at his finger, his eyes comically meeting at the corners and retracts his mouth from Seijuro’s finger.

"Hey!" Before Seijuro could stop him, he instead puts his own hand inside his mouth and bites down with all his force. An excruciatingly painful, screeching mewl comes out of Tetsuya's throat and he screams in his small thin voice, holding onto his hand while simultaneously bawling his eyes out. In a way, Seijuro was excited with this development.

"Ssh ssh, you're going to be okay." He says gently grasping Tetsuya's hand in his own as he ransacks the drawer with the other for a Band-Aid.

"There, there." Tetsuya was still crying so he didn't really pay much attention when Seijuro picked him and brought them to the sink to wash his hand with cold water. He had bit enough to break his skin, tiny drops of blood oozing from the wounds.

When the cold water soothes the damage, Tetsuya quiets down to watch it take away the red evidence, wincing when he anxiously flexed his fingers. Seijuro turns off the tap. "Let's dry it and put on the aid." He watches as Tetsuya tries to grasp the water that has disappeared behind the tap.

Seijuro gently dabs the small hand with a towel. "We're going to place this on the scab." He holds up the Band-Aid before carefully placing it around Tetsuya's hand.

"Good?"

Tetsuya still sobs as he holds his hand with the other. "It will be better in a while." Seijuro says and pats his head soothingly.

"Myau..." Tetsuya whimpers, tears escaping his eyes.

Seijuro smiles. "Want to see around my house?" This time Tetsuya doesn't hesitate and steps into his awaiting palm.

 

///  
Tetsuya quickly forgets that he had ever hurt his hand as they traipse around the house. Seijuro teaches him to chew and this time Tetsuya cautiously bites on the rice, getting the hang of it pretty soon. And though he could chew normally by the end of the day he still excitedly poured gobfuls of milk powder in his mouth. So Seijuro makes a note to bring him more powders like sweetened chocolate cocoa and mix them with the milk.

 

///  
By next week, Seijuro doesn't need to go down to his lab for measuring any inches Tetsuya might have grown because he's there sitting up in his bed -where he had slept- a bevy of inches taller and clearly uncomfortable and itchy in his too short and too tight clothes. This is the fastest spurt of growth he had ever shown. He's as big as a two year old.

"Tetsuya..."

"Myau?" He tilts his head in question. Not only had he burgeoned, he had picked up Seijuro's habits by instincts.

The experiment was a success. The hybrid was growing in response to the different stimuli. And since yesterday he had been exposed to a number of them, his growth had accelerated appreciatively.

"Can you jump?" Seijuro asks as he stands on the bed, Tetsuya automatically following him.

Seijuro jumps, a slight bounce of his feet. But it was enough for Tetsuya to perceive as he ducks his rear, a strange streak of determination in his slanted brows and eager eyes that were apathetic until yesterday. He jumps, more in the sense of the word than Seijuro expected him to, and higher, than a two year old ever could, due to his inherent feline reflexes.

"Excellent, Tetsuya." Seijuro encouragingly ruffles his head and sensitive ears, his tail that had been stale yesterday, wagging excitedly behind him.

"Nyaa~" He purrs and bewilders Seijuro when he adds, "Good! Good!"

He spoke!

"Tetsuya can you say something else? Like your name? My name?" He points to himself. "I'm Akashi Seijuro." He wanted to know even more about everything Tetsuya had picked up since yesterday.

Tetsuya opens his mouth, tongue twisting to pronounce his name. "A..aka..."

"Akashi Seijuro." Seijuro repeats patiently. "A..ka..shi."

"Aka..." Seijuro feels proud that Tetsuya was able to enunciate the first part of his surname without the need to dice it. "...shi. Akashi! Akashi!" Tetsuya bounces excitedly on his heels, his tail and ears twitching and swishing in obvious glee. His whole system showed how high he was just by being able to gain Akashi's appreciation and compliments. "Akashi!"

Seijuro couldn't stop himself from laughing even if he tried. In that moment, seeing Tetsuya so genuinely raptured was enough of a source for him to ignore that Tetsuya was only a hybrid produced in the lab. And was instead the source of his calm. The type he hadn't felt in a while. It was interesting enough that someone would be so happy just by learning his name alone. It was definitely not an everyday thing.

"Yes, I'm Akashi." Seijuro chuckles.

Tetsuya grins and holds his hand once more, for which he has established a penchant for. "Akashi, good."

Seijuro pretends he didn't know what he was doing when he pecks Tetsuya's forehead. A hybrid's forehead. "Tetsuya is good, too."

Tetsuya's face begins to grow red as they continue to stare at each other at such a close proximity which Seijuro recognizes as the hybrid blushing. He also seemed to want to speak as he struggles with his tongue but either didn't know how to or just gets embarrassed. He touches Seijuro's head around for a while, then he touches his own.

"I don't have these." Seijuro says while lightly caressing his furry black ears.

"No?" Tetsuya tilts his head again which was appearing to be a norm for whenever he asked a question.

"No. I have these." Seijuro holds both of Tetsuya's hands and lets him touch his human ears.

For some reason, Tetsuya's ears drop and he steps closer to awkwardly hug him. Seijuro was flummoxed. The hybrid didn't have any way to learn what a hug was but he acted on its instincts alone. Instincts that arose from the emotions he had surely been harboring for Seijuro since the beginning. Come to think of it, Seijuro was the first and only person who held him, whose warmth he had acclimated to. He perceived Seijuro as his guardian and protector since birth.

  
But for Seijuro it was different. This hybrid was an experiment and an invention. When he designed its preliminary code he included all the supreme alleles in it. If one was to be dominant and the other recessive, they'd retain strength. He included emotions too of course but the extent of their mutation and the hybrid's nature was far from what he theorized it to be. In a consequential way, the hybrid was a failure.

He removes Tetsuya from him as indifferently as he could without showing his disappointment evidently. He doesn't ask Tetsuya to follow him or stand outside the bathroom, awaiting him like some sort of loyal dog. Or to fall in step with him when he leaves for the kitchen to make coffee for himself.  
He sighs, watching Tetsuya standing by his side observing the counter tops, tail iffy, dancing behind him every now and then.

 Seijuro didn't think performing any sort of surgery could now alter his genotype or phenotypes for that matter. He tugs Seijuro's pajama pants and points towards the milk powder beside the sink.

"You can jump, right? Go get it for yourself."

Tetsuya jerks and stumbles when Seijuro sharply turns away, leaving him alone in the kitchen.

 "Akashi?"

 He didn't mean to be hostile but the pressure of failure was very dogmatic and to see it follow him around only fueled his sourness. However, the hybrid didn't quite perceive rejection as of yet, as it slowly and persistently approaches Seijuro.

 "Tetsuya... No good?" He asks after a few minutes of standing beside the coffee table in the living room, five steps away from him.

"Everything isn't about you." Seijuro says crossly.

"I didn't think I'd be designing a robot who followed me around." He rubs his temple.

"Tetsuya, go back to the room." If he would follow orders then at least, Seijuro can give him one to remove him from gallivanting in his periphery.

"Room?" Tetsuya tilts his head again, unsure of the command he has been given.

"Yes. There." Seijuro points to the door leading to his room. 

"Leave. Now."

 Tetsuya studies him and Seijuro just about gives up on him when Tetsuya’s ears flatten against his scalp after twitching uncertainly on his head for half a minute. He takes a step back and turns around to do as he was told to. He turns to look at Seijuro a good few times before he finally reaches the door, lingering there reluctantly, before disappearing for good.

Seijuro sags into the coach. Really, what was he supposed to do with it? Euthanize it? Everything about it was amiss. It didn't even grow like normal beings, relying on its emotions instead. How did the genes mutate itself so extremely? Or did he actually skip a sequence?  
There was no perfect way to tell or study the whole helix before it has trans mutated again. It will expire before he could complete his research and a new one couldn't be trusted to have the same characteristics. The hybrid was growing, its genes still in a perpetually unstable state, activating, deactivating.

He goes down to the basement and doesn't return until later at night. The house was dark and he was a tad-bevy worried about Tetsuya. He switches on the lights in the living room and his own room as he steps inside. 

"Tetsuya?"

 The hybrid was standing by the window, staring at the city lights, a scarf wrapped around his body. Seijuro had completely forgotten about his clothes. Some of the books from his shelf had migrated to his study table and the swivel chair was askew. He had probably tried to read.

Tetsuya turns to face him, grim eyes, wan face and Seijuro's eyes widen a fraction as he stands up on his feet, apparently kneeling before, to his full height. He was taller. If emotions were the stimuli as predicted, then that must mean he immensely felt the rejection. He looked like a five year old.

 "Does Akashi-kun hate me?" His speech was fluent and smooth, picketed with wistfulness.

 "Did you learn to read by yourself?" Seijuro asks instead.

 

He knew he was being derelict of Tetsuya but he needed to know. Because if it was as it seemed, it must mean that the hybrid had retained its intellect. Only that it was sensitized with his experiences.

Tetsuya glances at the books at his table. "Yes, I did. It was obfuscating but I realized I could read without much effort. It wasn't hard to speak after that."

  
If they replaced the genes for memory and comprehension with an aggrandized gene of..."Are you going to replace me?" Seijuro blinks. Tetsuya hadn't tilted his head.

"You only think of me as a Guinea pig, don't you? ...Master."

 Master... Seijuro's whole body felt pinpricked at the spot. Like tiny invisible needles were pinching and stabbing him from the inside out.

All his life, he had wanted a companion who could stay by his side unconditionally and accept him as he was with his superior intelligence. But somewhere along the way that ideology had changed in its core and when he saw the living hybrid in his hands, all he wanted was to herald it to the world so they'd acknowledge his absolution. So they'd bow down to him because he could give and take life at his will. When did he stop being wanting to be normal? Perhaps the moment he felt power in its crudest form, lying there in the palm of his hand.

Tetsuya had approached him in the meanwhile and was staring at him with the same expression of trepidation and anxiousness in his eyes. "Whose genes am I?"

Seijuro gulps. "My mother's."

"Am I like her?" He asks next.

Seijuro exhales a grim chuckle. "Not at all. Nothing alike."

Tetsuya presses a hand on his heart and solemnly purses his lips. "She loved master very much, didn't she?"

"Well, I never met her while I was conscious enough to deduce that." And then it hits him. His voice shakes initially when he asks,

 "Do..Do you...?"

Tetsuya smiles at him, it’s the smile he had seen in the photos framed in his childhood home, the ones he have in his possession.

 "Yes, Seijuro."

 Tetsuya places both his hands on his cheeks and pulls him closer into a hug.

It wasn't that Tetsuya knew how to, now Seijuro concludes, it was because of his mother. She had never been able to touch him ever since after his birth, falling into coma right after. But she must have wanted to. She must have loved him so much in all those years she had maybe heard him growing up, sitting beside her bed, holding her hand or touching her face or crying because father was too harsh on him.

"Remember Seijuro, no matter what you've become or if the world scorns you, your mother will always love you." Seijuro can catch the emotion in Tetsuya's voice, and even though it's not his mother, he hugs him back and imagines it's hers.

"O-kaa-san..." He chokes and hides himself in the crook of Tetsuya's neck.

"No..." Tetsuya says, caressing his hair. "…it's Kuroko Tetsuya."

Seijuro hugs him tighter. "Tetsuya."

Yes, it wasn't his mother but Tetsuya, her living memory and his own person.

"I may not be her but I will always love master unconditionally because I know he's a wonderful, brilliant and a very kind person. He can be an airhead and seems to have some sort of superiority complex, but I'll always stay by his side even if he was to not need me anymore." Seijuro makes an indignant noise in Tetsuya's neck.

"Even if he threw me away, I'll obstinately end up on his door until he gets things right."

"Thank you, Tetsuya.” He says and after a few seconds when he had calmed down and collected his emotions, he removes himself from Tetsuya's neck.

"...happy fifth birthday." Seijuro wishes with a teasing but honest smile. It may look like the most irrelevant of things to say but a part of Seijuro was alight because this…person was here beside him in this moment of weakness.

Like the kid he is, Tetsuya flushes and mumbles, "A birthday should have a cake and gifts. And you should get me five for each stage grown."

Seijuro flops down onto the carpet bringing Tetsuya with him whose flush deepens as he struggles to get free. "You're just going to be taller tomorrow."

Tetsuya gives him an annoyed pout. "Cats grow fast. You're the one who made me like this."

  
"I didn't think you'd be such a mutant." Seijuro says while scratching his ears.

Tetsuya purrs. 'Mmm...Nyaa~!”

Seijuro stops.

Tetsuya slaps a hand over his mouth.

"Pfft..." Seijuro couldn't stop himself from the fit of laughter that burst out like a cascade.

 "You know…I was wondering what would happen if I scratched your tail?"

"What?! No! Why did you make me like this?" Tetsuya whines, wrapping his tail around his waist and pushing away from him.

  
"Adults have their reasons." Seijuro says, tease in his tone, and puts Tetsuya down. "Find yourself something to wear from the closet.” He opens the wardrobe and shoves Tetsuya in. “I'm going to make us noodles."

He expected Tetsuya to grumble but his head has already vanished inside the clothes. So, Seijuro can only tell from his voice that he is smiling when he says, “Okay! Coming!”

Seijuro vaguely wondered what he was going to tell Shintarou and the others.

**Author's Note:**

> Thank you for reading~!!


End file.
